Caracterização genética e eficácia antibacteriana de nanopartículas de polipirrol frente a Staphylococcus aureus isolados de mastite em vacas e cabras no estado de Pernambuco, Brasil

Abstract

The aim of the present study was to characterize genetically isolates of Staphylococcus aureus (S. aureus) obtained from cows and goats with mastitis in Pernambuco state, Brazil. Additionally was evaluated the antibacterial efficacy of nanoparticles of polypyrrole (PPy) in water against biofilm producer or not S. aureus. For this, 150 isolates (123 from bovines and 27 from goats) were analyzed. The virulence factors involved in adhesion to host cells (fnbA/B and clfA/B), toxins (sea, - sei, tsst, hla and hlb), and capsular polysaccharide genes (cap5 and cap8) were amplified by PCR. A total of 138 isolates of S. aureus were evaluated for biofilm formation by spectrophotometry in microplates and Minimum Inhibition Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of nanoparticles of PPy were measured. The toxic potential, defined by the number of toxins genes per isolate, showed that goat’s isolates had a higher potential. The cap8 genotype had more virulence potential by the number of virulence genes per isolate. The cap5 genotype was most frequent (70.67%), especially in bovine’s strains. The MIC and MBC of S. aureus to PPy were found in 125μɡ/mL in all strains, independent of biofilm production or not. New control measures should be implement, especially in goats that the isolates circulating had a higher toxic potential. In view of the positive preliminary results of PPy nanoparticles, future studies should be performed to obtain a product that contributes to mastitis control.